class Aws::S3::EncryptionV2::EncryptHandler

def apply_cse_user_agent(context)
  if context.config.user_agent_suffix.nil?
    context.config.user_agent_suffix = EC_USER_AGENT
  elsif !context.config.user_agent_suffix.include? EC_USER_AGENT
    context.config.user_agent_suffix += " #{EC_USER_AGENT}"
  end
end

def apply_encryption_cipher(context, cipher)
  io = context.params[:body] || ''
  io = StringIO.new(io) if io.is_a? String
  context.params[:body] = IOEncrypter.new(cipher, io)
  context.params[:metadata] ||= {}
  context.params[:metadata]['x-amz-unencrypted-content-length'] = io.size
  if context.params.delete(:content_md5)
    raise ArgumentError, 'Setting content_md5 on client side '\
      'encrypted objects is deprecated.'
  end
  context.http_response.on_headers do
    context.params[:body].close
  end
end

def apply_encryption_envelope(context, envelope)
  if context[:encryption][:envelope_location] == :instruction_file
    suffix = context[:encryption][:instruction_file_suffix]
    context.client.put_object(
      bucket: context.params[:bucket],
      key: context.params[:key] + suffix,
      body: Json.dump(envelope)
    )
  else # :metadata
    context.params[:metadata] ||= {}
    context.params[:metadata].update(envelope)
  end
end

def call(context)
  envelope, cipher = context[:encryption][:cipher_provider]
   .encryption_cipher(
     kms_encryption_context: context[:encryption][:kms_encryption_context]
   )
  context[:encryption][:cipher] = cipher
  apply_encryption_envelope(context, envelope)
  apply_encryption_cipher(context, cipher)
  apply_cse_user_agent(context)
  @handler.call(context)
end